A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 6135-00-248-4102
NSN 5910-01-556-4278
NSN 6105-01-094-8228
NSN 6130-01-483-0514
NSN 7035-00-763-6180
NSN 4140-00-526-4505
NSN 5975-00-505-2626
NSN 5855-01-031-4729
NSN 5935-00-371-0523
NSN 6650-01-463-0915
NSN 6620-01-116-3983
NSN 6105-01-225-1539